Measuring device and shaping device

ABSTRACT

A measurement device is configured to measure a three-dimensional shape of an object for measurement. The measurement device includes a projector, an imager, an identifier, and a calculator. The projector is configured to project a plurality of light lines onto the object for measurement. The imager is configured to capture an image of the object for measurement on which the plurality of light lines are projected. The identifier is configured to identify a projection condition of the light lines based on shaping information of the object for measurement. The calculator is configured to calculate a plurality of line shapes from the image captured by the imager, based on the projection condition.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application claims priority under 35 U.S.C. § 119 toJapanese Patent Application No. 2019-050516, filed on Mar. 18, 2019. Thecontents of which are incorporated herein by reference in theirentirety.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to a measuring device and a shapingdevice.

2. Description of the Related Art

Currently, shaping devices or what is called three-dimensional printerdevices (3D printer devices) for shaping three-dimensional objects basedon input data are known in the art. Also, 3D printer devices includingthree-dimensional shape measurement functions for acquiring theshape/contours of the molded object are known in the art.Three-dimensional shape measuring functions exert minimal effects on theshaping process and therefore non-contact type three-dimensional shapemeasuring functions are often utilized. Non-contact typethree-dimensional shape measurement functions such as the opticalcutting method and pattern irradiating method are known.

Japanese Unexamined Patent Application Publication No. 2017-15456discloses a measurement system capable of simultaneously irradiating theobject for measurement with a plurality of slit laser lights andmeasuring the three-dimensional coordinates with good efficiency andhigh accuracy.

However, when acquiring the shape of the object for shaping, themeasurement system of Japanese Unexamined Patent Application PublicationNo. 2017-15456 requires shortening the measurement time to avoid effectson the shaping process.

SUMMARY OF THE INVENTION

According to an aspect of the present invention, a measurement device isconfigured to measure a three-dimensional shape of an object formeasurement. The measurement device includes a projector, an imager, anidentifier, and a calculator. The projector is configured to project aplurality of light lines onto the object for measurement. The imager isconfigured to capture an image of the object for measurement on whichthe plurality of light lines are projected. The identifier is configuredto identify a projection condition of the light lines based on shapinginformation of the object for measurement. The calculator is configuredto calculate a plurality of line shapes from the image captured by theimager, based on the projection condition.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1A to 1C are system structural drawings of the 3D shaping systemaccording to a first embodiment;

FIG. 2 is a hardware structural drawing of the information processingterminal installed in the 3D shaping system according to the firstembodiment;

FIG. 3 is a function block diagram of each function implemented by theCPU of the information processing terminal by executing the shapingcontrol program;

FIGS. 4A to 4C are drawings illustrating an example of the image of theobject for measurement captured by the imager, on which a plurality oflight lines are projected;

FIGS. 5A to 5C are drawings for describing the operation for identifyingprojection conditions of the light lines;

FIGS. 6A to 6C are drawings illustrating an image captured of the objectfor measurement by projecting the light lines in the 3D shaping systemaccording to a second embodiment;

FIGS. 7A to 7C are drawings illustrating a captured image of the objectfor measurement by projecting the light lines in the 3D shaping systemaccording to a third embodiment.

The accompanying drawings are intended to depict exemplary embodimentsof the present invention and should not be interpreted to limit thescope thereof. Identical or similar reference numerals designateidentical or similar components throughout the various drawings.

DESCRIPTION OF THE EMBODIMENTS

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the presentinvention.

As used herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise.

In describing preferred embodiments illustrated in the drawings,specific terminology may be employed for the sake of clarity. However,the disclosure of this patent specification is not intended to belimited to the specific terminology so selected, and it is to beunderstood that each specific element includes all technical equivalentsthat have the same function, operate in a similar manner, and achieve asimilar result.

An embodiment of the present invention will be described in detail belowwith reference to the drawings.

An embodiment has an object to provide a shaping device and ameasurement device capable of measuring the three-dimensional shape ofthe object for measurement with high speed and with high accuracy.

The embodiments of the 3D shaping system of the embodiments of themeasuring device and shaping device are hereinafter described whilereferring to the accompanying drawings.

System Structure

First of all, FIGS. 1A to 1C are system structural drawings of the 3Dshaping system 1 according to a first embodiment. Hereafter, forpurposes of convenience, the following description proceeds by referringto the height direction of the 3D object as the z axis direction, andthe surface intersecting the z axis as the xy plane. Hereafter, the 3Dshaping system 1 is described by the fused filament fabrication methodusing filament as one example of the shaping material however thepresent invention is not limited to this method and 3D shaping systemsutilizing a variety of methods are allowable.

As illustrated in FIG. 1A, the 3D shaping system 1 includes a shapingdevice 100 that shapes the 3D object for shaping, and an informationprocessing terminal 150. The information processing terminal 150 sendsshape data for the 3D object for shaping to the shaping device 100. Theshaping device 100 shapes the 3D object for shaping based on shape datafor the object for shaping that is received from the informationprocessing terminal 150.

The information processing terminal 150 may operate as a controller tocontrol the processing to operate the shaping device 100, or thefunctions of this information processing terminal 150 may be embeddedinto the shaping device 100 for operation. Namely, the shaping device100 and the information processing terminal 150 may be individuallyoperated as physically separate devices, or integrally operated as theshaping device 100.

As illustrated in FIG. 1B, the shaping device 100 includes a shaper 210capable of movement in parallel with the xy plane, and a shaping plate330. The shaping device 100 dispenses shaping material (filament) 140over the shaping plate 330 from the shaper 210 and forms a layered shapeon the xy plane of the 3D object for shaping. The shaping device 100shapes one layer of a shaping layer of the 3D object for shaping bydrawing one-dimensional lines within the same plane.

When shaping of one layer of the shaping layer is complete, the shapingdevice 100 lowers the shaping plate 330 by just a one-layer heightportion (lamination pitch) along the z axis direction. The shapingdevice 100 subsequently drives the shaper 210 the same as for the firstlayer to shape the second layer of the shaping layers. The shapingdevice 100 repeats these operations to form the layer laminations andshapes the 3D object for shaping.

The shaping device 100 moves the shaper 210 along the xy plane and asdescribed by the example, moves the shaping plate 330 along the z axis.However, the above described structure does not limit the presentembodiment and other structures may be utilized.

As illustrated in FIG. 1C, the shaping device 100 includes a shapesensor 310 as a measurement device for measuring the shaping layerduring shaping or the shape of the 3D object after shaping. The shapesensor 310 measures dimensions of the x axis, the y axis, and the z axisdirections of the 3D object for shaping, etc.

An infrared sensor, a camera device, or a 3D measurement sensor (e.g.,optical cutting profile sensor) may for example be utilized as the shapesensor 310. In other words, the shaping device 100 also functions as ascanning device. In the first embodiment, an example of the 3Dmeasurement sensor (e.g., optical cutting profile sensor) utilized asthe shape sensor 310 is described.

As subsequently described using FIG. 3, the shape sensor 310 (opticalcutting profile sensor) includes at least a projector 300 and an imager301. The projector 300 projects a plurality of light lines onto theobject for measurement. More specifically, the projector 300 projectspattern light rays onto the object for measurement. The imager 301captures images of the objects for measurement that the projector 300projects the light lines on. More specifically, the imager 301 acquiresimage data (camera images) of 2D images of the object for measurementthat pattern light ray is projected upon.

As illustrated in FIG. 1C, the shape sensor 310 may measure the shape ofthe shaping layer while interlocked with the shaping operation forexample of the shaper 210. The shape sensor 310 may measure the shape ofthe shaping layer as each single layer of the shaping layer is formed.The timing and range for the shape sensor 310 to measure the object forshaping can be optionally set.

Hardware Structure of the Information Processing Terminal

FIG. 2 is a structural drawing of the hardware for the informationprocessing terminal 150. As illustrated in FIG. 2, the informationprocessing terminal 150 includes a central processing unit (CPU) 151, aread only memory (ROM) 152, a random access memory (RAM) 153, a harddisk drive (HDD) 154, an operating interface (operating I/F) 155, and acommunicator 156. A shaping control program that performs shapingcontrol of the shaping device 100 is stored in the HDD 154.

Function of the Information Processing Terminal

As illustrated in FIG. 3, the CPU 151 executes each function of ashaping controller 200, a shape measurement controller 220, and a shapedata calculator 250 by executing the shape control program stored in theHDD 154.

The shaping controller 200 controls the shaping operation of the shapingdevice 100 based on the shape data. Specifically, the shaping controller200 generates shaping commands based on the shape data and supplies theshaping commands to the shaper 210 of the shaping device 100. Theshaping commands are commands stipulated by the shaper 210 and aregenerally commands that control the shaping process information forsupplemental shaping.

The shape measurement controller 220 controls the shape sensor 310.Specifically, the shape measurement controller 220 first of all suppliesirradiation commands to the projector 300 of the shape sensor 310 toirradiate the light lines onto the object for measurement. The projector300 generates light rays in a linear state and projects them onto theobject for measurement. As only a single example, in the case of the 3Dshaping system 1 according to the first embodiment, a plurality of lightlines are projected. By changing the irradiation angle of one lightline, a projection state with the light lines may be projected, and thelight lines may be generated by installing a plurality of light sourcesthat project a single light line. The light lines may also be generatedby utilizing a planar projector function.

The shape measurement controller 220 supplies imaging commands to theimager 301 of the shape sensor 310 to capture images of the object formeasurement on which light lines are projected. The imager 301 capturesimages of the object for measurement on which the light lines areprojected and supplies this image data to the shape data calculator 250.To capture the projected light lines as a single image, the shapemeasurement controller 220 generates imaging command for the imager 301that are synchronized with projection commands to the projector 300.

The shape data calculator 250 calculates the shape data. The shape datacalculator 250 is one example of an identifier and a calculator. Theidentifier identifies projection conditions for the light lines based onshaping information of the object for measurement. The calculatorcalculates a plurality of line shapes from the image captured by theimager based on the projection conditions. The shape data calculator 250identifies patterns for the light lines in the image data by utilizingthe shape data, and for example calculates 3D data (shape data) of theobject for measurement by the optical cutting method.

Calculation Operation for Shape Data

FIGS. 4A to 4C are drawings illustrating one example of the image of theobject for measurement captured by the imager 301 and on which the lightlines are projected. Among these, FIG. 4A illustrates an outer view ofthe object for measurement 320 formed on the shaping plate 330. Incontrast to this type of object for measurement 320, as illustrated inFIG. 4B, the projector 300 projects the light lines 340, 341 (as oneexample, two light lines) onto the object for measurement 320 and theimager 310 performs image capture. The projector 300 projects two of thelight lines 340 and the light line 341 that have different lightconditions. This light line may be projected simultaneously or may beprojected by time sharing for each condition. The number of light linesprojected by the projector 300 is not limited to two lines.

The imager 310 captures images of the object for measurement 320 onwhich the light lines 340, 341 are projected and so can in this waygenerate image data 350 as illustrated for example in FIG. 4C. The shapedata calculator 250 converts the image data 350 into distance data basedon the what is called optical cutting method. Generally, when measuringdistance using the optical cutting method, one light line is irradiatedand the distance calculation processing is performed based on that imagedata.

In contrast, in the 3D shaping system 1 according to the firstembodiment, images of the projected light lines 340, 341 can be acquiredand the distance data of the light lines 340, 341 is calculated in onebatch. Therefore, this calculation requires identifying irradiationconditions of the light lines from the projection patterns of the lightlines contained in the image data 350. The shape data calculator 250utilizes shape data to identify projection conditions of the light lines340, 341 that are projected onto the object for measurement 320.

In other words, the object for measurement 320 is an object for shapingthat is shaped by the shaping device 100 and therefore the shape datacalculator 250 can acquire shape data acquired under ideal conditions inadvance prior to measurement. The shape data calculator 250 alsocalculates the projected line pattern image (predictive pattern data)acquired when the light line for that ideal shape is projected. Theshape data calculator 250 further calculates the predictive pattern datawhile adding the “assumed range of shape error” for error that isdetermined by the shaping performance of the shaping device 100.

Identifying Operation for Projection Conditions of Light Line

The operation for isolating and arranging the projection information ofthe light lines contained in the image data 350 and for identifyingprojection conditions of the light lines is described next. FIG. 5includes drawings for describing the operation for identifyingprojection conditions of the light lines. As described above, the shapedata calculator 250 generates a predictive pattern data 360 asillustrated for example in FIG. 5A that predicts the image observedunder light lines projected for each of the projection conditions by wayof the shape error within the assumed range and the ideal shape data forthe object for measurement 320.

By projecting the two light lines 340, 341 on the object for measurement320, the predictive patterns 361, 362 for two projection conditions canbe obtained as illustrated in FIG. 5A. The predictive patterns 361, 362include the error within the assumed range as described above. The widthof the light lines is therefore larger than the observed light lineswidth.

In other words, the light lines 340 projected onto the object formeasurement 320 under the first projection condition observed in thearea 361 illustrated in FIG. 5A, can be predicted based on thepredictive pattern. Specifically, by comparing the predictive patterndata, with the image data illustrated in FIG. 6B, the shape datacalculator 250 can identify line L2, line L4, and line L6 as projectionresults from projecting the light lines 340 under a first projectioncondition. The shape data calculator 250 can in the same way, identifyline L1, line L3, and line L5 as projection results from projecting thelight lines 341 under a second projection condition.

The object for measurement 320 can in this way be shaped by the shapingdevice 100 based on shaping data so that projection conditions for thelight lines 340, 341 projected onto the object for measurement 320 canbe isolated using the shaping data. The shape data (Z direction, heightdata) of the lines can therefore be obtained in one batch based on oneround of imaging data.

Advantageous Effects of First Embodiment

As clarified in the above description, the 3D shaping system 1 accordingto the first embodiment is capable of measuring two line shapes with oneimage data by using the light lines 340, 341 and without having toinstall new hardware for identifying projection conditions for the lightlines. High-speed and low-cost shape measurement can therefore beachieved. The shape data calculator 250 can calculate distance data ofthe light lines 340, 341 in one batch and can therefore shorten themeasurement time (speeding up).

Second Embodiment

The 3D shaping system according to a second embodiment is describednext. In the case of the example for the 3D shaping system 1 accordingto the first embodiment, one projector 300 projects a plurality of lightlines 340, 341. In contrast, in the example of the 3D shaping systemaccording to the second embodiment, a plurality of projectors projectone light line. The first embodiment described above and the secondembodiment described below, differ only in this point. Therefore, only adescription of the differences between both embodiments is given andredundant descriptions are omitted.

FIG. 6 includes drawings illustrating the captured image of the objectfor measurement by projection of the light lines in the 3D shapingsystem according to the second embodiment. Among these, FIG. 6Aillustrates an outer view of the object for measurement 320 that isshaped on the shaping plate 330. In the case of the 3D shaping systemaccording to the second embodiment as illustrated in FIG. 6B, there arefor example two projectors 330. The light lines 340, 341 from therespective projectors 330 are projected onto the object for measurement320, and an image is captured by the imager 310.

The shape data calculator 250 can identify line L2, line L4, and line L6as projection results from projecting the light line 340 under a firstprojection condition by comparing the above described predictive patterndata, with the image data illustrated in FIG. 6C. The shape datacalculator 250 can in the same way, identify line L1, line L3, and lineL5 as projection results from projecting the light line 341 under asecond projection condition.

This type of 3D shaping system according to the second embodiment, thesame as the first embodiment described above, is capable of isolatingthe projection conditions for the light lines 340 and 341 projected ontothe object for measurement 320 by utilizing the shaping data. The shapedata (Z direction, height data) of the lines can therefore be obtainedin one batch based on one round of imaging data to obtain the sameeffect as the first embodiment.

Third Embodiment

The 3D shaping system according to a third embodiment is described next.In the case of the example for the 3D shaping system according to thesecond embodiment described above, a plurality of projectors eachproject one light line. In contrast, in the 3D shaping system accordingto the third embodiment, a plurality of projectors each project aplurality of light lines. The second embodiment described above and thethird embodiment described below, differ only in this point. Therefore,only a description of the differences between both embodiments is givenand redundant descriptions are omitted.

FIGS. 7A to 7C are drawings illustrating the image captured of theobject for measurement by projection of light lines in the 3D shapingsystem according to the third embodiment. Among the drawings, FIG. 7Aillustrates an outer view of the object for measurement 320 being shapedon the shaping plate 330. In the case of the 3D shaping system accordingto the third embodiment, there are for example two projectors 330 asillustrated in FIG. 7B. One projector 330 projects two light lines 340,342 to the object for measurement 320, and the other projector 330projects two light lines 341, 343 to the object for measurement 320. Theimager 310 then captures images of the object for measurement 320 onwhich light from each light line 340 through 343 is projected.

The shape data calculator 250 can identify line L4, line L8, and lineL12 as projection results from projecting the light line 340 under afirst projection condition by comparing the predictive pattern data,with the image data illustrated in FIG. 7C. The shape data calculator250 can identify line L3, line L7, and line 11 as projection resultsfrom projecting the light line 342 under a first projection condition.

The shape data calculator 250 can in the same way identify line L1, lineL5, and line L9 as projection results from projecting the light line 341under a second projection condition, and identify line L2, line L6, andline 10 as projection results from projecting the light line 343 under asecond projection condition.

This type of 3D shaping system according to the third embodiment, thesame as the second embodiment described above, is capable of isolatingthe projection conditions for the light lines 340 through 343 projectedonto the object for measurement 320 by utilizing the shaping data. Theshape data (Z direction, height data) for the lines can therefore beobtained in one batch based on one round of image data to obtain thesame effect as each of the above described embodiments.

Finally, each of the above described embodiments is provided as a singleexample and is not intended to limit the range of the present invention.Each of these novel embodiments can be implemented in other variousforms and all manner of omissions, substitutions, and changes may beimplemented without departing from the scope and spirit of the presentinvention. Various three-dimensional shaping methods are known in theart for example such as the fused filament fabrication (FFF) method,material jetting method, binder jetting method, selective lasersintering (SLS) method (or selective laser melting (SLM) method),stereolithography (laser method or digital light projector (DLP)method), however, the present invention applies to all of these 3Dshaping methods and the above described effects can be obtained in allof these cases. The embodiments and the modifications of the embodimentsare included in the range and intent of the invention, and are alsoincluded in the range of the claims of the invention or a rangeconsistent with the invention.

An embodiment renders the advantageous effect that measuring thethree-dimensional shape of the object for measurement can be measuredwith high speed and good accuracy.

The above-described embodiments are illustrative and do not limit thepresent invention. Thus, numerous additional modifications andvariations are possible in light of the above teachings. For example, atleast one element of different illustrative and exemplary embodimentsherein may be combined with each other or substituted for each otherwithin the scope of this disclosure and appended claims. Further,features of components of the embodiments, such as the number, theposition, and the shape are not limited the embodiments and thus may bepreferably set. It is therefore to be understood that within the scopeof the appended claims, the disclosure of the present invention may bepracticed otherwise than as specifically described herein.

The method steps, processes, or operations described herein are not tobe construed as necessarily requiring their performance in theparticular order discussed or illustrated, unless specificallyidentified as an order of performance or clearly identified through thecontext. It is also to be understood that additional or alternativesteps may be employed.

Further, any of the above-described apparatus, devices or units can beimplemented as a hardware apparatus, such as a special-purpose circuitor device, or as a hardware/software combination, such as a processorexecuting a software program.

Further, as described above, any one of the above-described and othermethods of the present invention may be embodied in the form of acomputer program stored in any kind of storage medium. Examples ofstorage mediums include, but are not limited to, flexible disk, harddisk, optical discs, magneto-optical discs, magnetic tapes, nonvolatilememory, semiconductor memory, read-only-memory (ROM), etc.

Alternatively, any one of the above-described and other methods of thepresent invention may be implemented by an application specificintegrated circuit (ASIC), a digital signal processor (DSP) or a fieldprogrammable gate array (FPGA), prepared by interconnecting anappropriate network of conventional component circuits or by acombination thereof with one or more conventional general purposemicroprocessors or signal processors programmed accordingly.

Each of the functions of the described embodiments may be implemented byone or more processing circuits or circuitry. Processing circuitryincludes a programmed processor, as a processor includes circuitry. Aprocessing circuit also includes devices such as an application specificintegrated circuit (ASIC), digital signal processor (DSP), fieldprogrammable gate array (FPGA) and conventional circuit componentsarranged to perform the recited functions.

What is claimed is:
 1. A measurement device configured to measure athree-dimensional shape of an object for measurement, the measurementdevice comprising: a projector configured to project a plurality oflight lines onto the object for measurement; an imager configured tocapture a single image of the object for measurement on which theplurality of light lines are projected; and processing circuitryconfigured to identify a projection condition of the light lines basedon shaping information of the object for measurement, the projectioncondition includes predictive patterns of the light lines based on anideal shape of the object and shape error; and calculate a plurality ofline shapes from the single image captured by the imager, based on theprojection condition.
 2. The measurement device according to claim 1,wherein the projector comprises a plurality of projectors, and each ofthe plurality of projectors is configured to project a light line of theplurality of light lines onto the object for measurement.
 3. Themeasurement device according to claim 1, wherein the projector comprisesa plurality of projectors, and each of the plurality of projectors isconfigured to project at least two of the plurality of light lines ontothe object for measurement.
 4. The measurement device according to claim1, wherein the processing circuitry is configured to calculate theplurality of line shapes using an optical cutting method.
 5. A shapingdevice comprising: a shaper configured to perform three-dimensionalshaping of an object for measurement based on shaping information; and ameasurement device configured to measure a three-dimensional shape ofthe object for measurement; the measurement device comprising: aprojector configured to project a plurality of light lines onto theobject for measurement; an imager configured to capture a single imageof the object for measurement on which the plurality of light lines areprojected; and processing circuitry configured to identify a projectioncondition of the plurality of light lines based on the shapinginformation of the object for measurement, the projection conditionincludes predictive patterns of the light lines based on an ideal shapeof the object and shape error; and calculate a plurality of line shapesfrom the single image captured by the imager based on the projectioncondition.